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A conservation-dependent species is a species which has been categorised as "Conservation Dependent" ("LR/cd") by the International Union for Conservation of Nature, i.e. as dependent on conservation efforts to prevent it from becoming threatened with extinction. Such species must be the focus of a continuing species-specific and/or habitat-specific conservation programme, the cessation of which would result in the species qualifying for one of the threatened categories within a period of five years. The category is part of the IUCN 1994 Categories & Criteria (version 2.3), which is no longer used in evaluation of taxa, but persists in the IUCN Red List for taxa evaluated prior to 2001, when version 3.1 was first used. Although using the 2001 (v3.1) system these taxa are classed as near threatened, but those that have not been re-evaluated remain with the "Conservation Dependent" category. Examples of conservation-dependent species include the Pyrenean chamois, leopard shark, black caiman, and bristlecone fir. There are 402 taxa (148 animals and 254 plants) in the 2006 IUCN Red List still classified as conservation dependent, all last evaluated in 2000 or prior. The animal taxa are made up of 110 species, 33 subspecies (all mammals), 4 species populations, 1 subspecies stock (blue whale North Pacific stock〔http://www.redlist.org/search/details.php?species=2482〕), and the plant taxa are made up of 238 plant species, 10 subspecies, and 6 varieties. Excluding subspecies and subpopulations, there are 63 mammals, 14 gastropods, 12 ray-finned fish, 9 crustaceans, 5 bivalves, 3 reptiles, 3 insects, and 1 shark with this classification. 59 species are listed as terrestrial, 25 freshwater, 19 marine, and 7 both terrestrial and freshwater. This last group (terrestrial & freshwater) includes crocodilian〔http://redlist.org/search/details.php?species=13053〕 and turtle species. The largest class of plants with this status is Magnoliopsida (196 species, 7 subspecies, 3 varieties), followed by Conifers (25 sp, 3 ssp, 1 var), and Liliopsida (17 sp, 2 var), which together make up all 254 conservation dependent plant taxa. In this category, only mammal taxa have population trends which are evaluated and known. The southern right whale is the only conservation dependent species evaluated with an increasing population. Additionally, 14 species have a stable population, and 19 are decreasing. The remaining species have unknown or unevaluated trends. Of the mammal subspecies with evaluated and known trends: 2 increasing, 10 stable, and 9 decreasing. The two shark taxa are the only non-mammals with an evaluated trend, however the result is merely "uncertain or unknown". == Examples == Examples of conservation-dependent animals include: *Common bent-wing bat *Black caiman *Masai giraffe *Mexican pronghorn, now classed as least concern 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Conservation-dependent species」の詳細全文を読む スポンサード リンク
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